Good work on the practice tests, moneymango! And yes, you're definitely overthinking the GMAT scoring algorithm... but that can be kind of fun, so let me help you overthink.
You're absolutely right: the same (very small) number of errors can lead to a variety of different scores on the verbal section. I've seen GMATPrep verbal tests with exactly one error that resulted in scores of 45, 46, 47, and 48. So getting 40 out of 41 correct can be a fairly wide range of scores. Crazy, right?
As random as it may seem, the scoring oddities are a byproduct of the adaptive algorithm. For example, question #5 is likely to be substantially easier than question #41, if we assume that you got everything else right. At question #5, you've only gotten four questions right, so you're not necessarily going to see the toughest question in the bank--and if you miss it, the scoring system will punish you more than it would if you only missed (the presumably very difficult) question #41.
So all else being equal, you'll lose more points for missing questions early in the section than later in the section. It doesn't mean that the guy who only misses question #5 is performing as well as the guy who misses only question #41, since the two test-takers are likely to see a somewhat different set of questions. For the first guy, question #6 won't necessarily be quite as hard as the second guy's version of question #6, and the scores will be slightly different as a result. So the placement of your misses matters, even if you're doing really really well.
I hope that made some sense. In any case, you seem to be on track, and if you get everything right, you won't have to worry about the GMAT scoring system at all.